1. Field of the Invention
The present invention relates to an image forming apparatus for forming images on sheets in response to a plurality of print jobs and performing post-processing of the sheets on which the images have been printed.
2. Description of the Related Art
Some known image forming apparatuses temporarily halt the processing of a job currently being processed to allow a subsequent job to interrupt the processing of the job currently being processed (refer to, for example, Japanese Patent Laid-Open No. 11-191050). Japanese Patent Laid-Open No. 11-191050 also describes that, when an interruption occurs, an image forming apparatus inquires to a submitter of the job currently being processed whether the submitter will allow the interruption from the subsequent job so as to handle the interruption in accordance with the answer from the submitter.
Additionally, some known image forming apparatuses identify the number of the unprocessed pages of the job currently being processed and the number of pages of an interrupting job so as to determine whether to allow the interruption on the basis of the identified numbers (refer to, for example, Japanese Patent Laid-Open No. 8-44515).
However, these known image forming apparatuses do not consider the output paper processing setting (post-processing of sheets), for example, stapling and punching of the sheets. Accordingly, if, for example, an interrupting job has an output paper processing setting, that job could require a longer processing time than an interrupted job. Therefore, a decision made to accept the interruption in this scenario makes no sense, which is a problem.
Furthermore, suppose that jobs which each have only a few pages and have no output paper processing setting are submitted in quick succession after a job having a post-processing setting is submitted. In this case, if these subsequent jobs which have no post-processing setting are processed first, the process of the interrupted job which has a post-processing setting is continuously postponed. Thus, the interrupted job is not completed.